Process for improving the whiteness or color of materials and products resulting therefrom



Patented May 26, 1953 PROCESS FOR IMPROVING THE WHITENESS OR COLOR OF MATERIALS AND PRODUCTS RESULTING THEREFROM John David Kendall and George Frank Duffin, Ilford, England, assignors to Ilford Limited, Ilford, England, a British company No Drawing. Application May 29, 1950, Serial No. 165,116. In Great Britain June 3, 1949 13 Claims. (Cl. 95-7) OFFICE This invention relates to a process for the improvement of natural or synthetic fibrous ma terials and of films of natural or synthetic c01- loid materials. Within these terms are to be unz are those in which the absorption maximum does not exceed 3900 A.

The foregoing definition of the compounds does not include compounds in which R1 or Arc 5 dfersfitlood tetxtlle materials generally, 1n till: ntains a mtro substltuent, or 1n which An cong g mgg g gg z' z ifi gg 3 g z tains a sulphonic carboxylic nitro or cyano group Y since those compounds do not fluoresce. or of synthetic materials such as regenerated Compounds of the foregoing formula in which cellulose, cellulose nitrate, cellulose acetate, cellu- R1 or the group An are hydrocarbon radicleslose propionate cemtlose butyrate and mixed 10 containing substituent carboxylic or sulphonic celulose esters as, for instance, cellulose acetateacid groups are for many purposes particularly ti gi a s ?g z fg; favourable, since they form alkali metal and amg e riv tiv eg sui l i as vi fiyl esi ei's :02:5 iilo d s moniumsaltslwhich are substantive to pracmcany the whole range of fibresand films referredto 23 g i polymeng 9 1 lmatenalg p i above. The free carboxylic and sulphonic acids gi i fi g iud d pogntiers 1 fib l m;- are substantive to protein and polyamlde fibres teriais sllch 22 1 g d g g gfi i z and films, but for the other materials, e. g. cellu losic materials such as cotton and paper, an $2135 :zmgg zf z i gf i ggfi i gi %gg cellulose acetate materials, the alkali salts are generally preferred. arias 221:3212?marria es: 5"? of ma be used in accor ance wi h e resen nfilms of cellulose acetate, cellulose nitrate, cellu-- veniion p lose acetate-butyrate and the like, or formed M.P.,C from compacted fibres, e. g. paper, cardboard, 25 l g- %p y l ps ra e felt and the like, or from natural colloids such j f l f f gggggfgg as gelatin. 1-m-tolyl-3-phenyl pgrazoline 183 The foregoing materials and materials of simil-ygfigggi-gyf ggg gggg Fifi 3 lar character are hereinafter referred to for brevggipgenyl-g-mitlliyll ram iine g H 1 V 1p eny -po y pyrazo me my as fipres films 1: -diphenyl-3-p-methoxyphenyl pyrazo1ine -M- 142 According to the present invention a process 1:5-6 phenyl-3-p-eth0xyphenyl pyraz011ne 13% for improving fibres and films comprises applyiz2 itfifitiiii?t ititiiit fitlh ttitttie:::::::: its ing thereto a small quantity Of a. fluorescent 00m- 1 :l5-dipl1enyl-3-(p-ethoxy m -.methyl)phenyl pyrazo- 13 c ine I 5 pound of the genera-'1 'lormula" 1-phenyl-3 5-di(p-ch1orphenyl)phenyl pyrazoline 151 HZO- C AU 1: 3-diphenyl-5-p-methoxyphenyl pyrazoline 124 l.-phenyl-3-p-methoxyphnyl-5-p-tolyl pyrazoline 127 R1 1-pheny1-3-p-tolyl-5-p-methoxypheny1 pyrazoline 141 1-phenyl-3 5-di(p-methoxy)phenyl yrazohne 147 1 4-di(1' 3'-diphenyl pyrazolinyl-o)benzene 290 Examples of water-soluble compounds which i 40 can be used are:

2 wherein R1 is a' 'hydroge'n'atom, hydrocarbon kfigiifilg fifigfifififig1it?t;onn roup or substitutedhydrocarbon group, An 1s l-g-p fi y u p ggl sg g-g yl igggg .--supope y-- y-- y anaromatic residue, e. g. phenyl or naphthyl, I p su1ph0phenyl 31,401yl 5 phem,lpymzoline which may contain any of the substituents hyl-psulgfiopgenyl-gg-nigthoiiylphfliylgihleiiyl pg-lz'ilziollne n-p-su op eny- -e oxy eny -o-p e y pyr ne droxy F hydFoxya'lkyl' p hydrocar' 1 -sulphophenyl-3-p-phenoxyphenyl-5-phenyl pyrazoline bon-substituted-ammo or acylammo groups or 1-p-Su%pg0plfienyl-g-(g-phingl)phiiilyl iplhenyil pyrazolline .-p-su p op eny -p eny p-me oxyp eny pyrazo me halogen atoms and Am 15 an aromatic nucleus 1w henyl-s- ;t0iy1-5- -methox hen q pyrazoline which may contain any substituent groups, e. g. llrp isliillzlll ophenlylt-lli :12-(11(1nethgxyp{1eny1) r z i le 1 -p-su p op eny -p eny -pyrazo my enzene substltuent hydrocarbon hydroxy l by l-m-sulphophenyl 3:5-di(p-chlorphenyl) pyrazoline droxyalkyl, ammo, hYdIOCEtIbOIl SUbSlJliUlZGdl-m-sulplfiopiienyl-g-(gghfinyl){)henyl-5fphenyl pyrazolme ..-m-sup op eny 2 1p eny pyrazo 1116 Su1phoI nc carboxyh? or cyano v Hp-methyl-m-sulpho)phenyl-3 5-diphenyl pyrazoline groups, WhlOh compound is colourless in aqueous i inetliyll-os ulghgflillienylg 59 111 11 fiiyralzolme 1,

u -sup 0- 1 1c or p eny- :o- 1 eny pyrazo me or alcohohc solutlon- By term T 2 1-(4 8-disulphonaphthyl-2l-3 5-diphenyl pyrazoline less in aqueous or ethyl alcoholic solution 1s 5 1-p-sulphophen yl-3pl1enyl-5-a-furylpyrazohne meant that a solution of the compound in water 5 1 Pymzohne or ethyl alcohol has an absorption maximum not greater than 4000' A. The preferre d compounds 1-p-to1yl-3-phenyl-5-o-sulphopl1enyl pyrazoline l.-p-anetamidophenyl-3-pheny1-5-0-sulphophenyl pyrazoline The preferred compounds according to the" present invention are those in which the pyrazoline contains a sulphophenyl group in the 1-posi tion and contains in the 3- and 5-positions phenyl groups or substituted phenyl groups.

The compounds may be prepared by various methods. One method is described in co-pending application Serial No. 165,118, filed on even date herewith. A. second method consists in the condensation of a Mannich reaction product (ob tained from an acetophenone with formaldehyde and an amine) with an aryl hydrazine, and a third method is the condensation of a ketone of the type Ar-CO-C(R)=CHz with an aryl hydrazine.

Compounds of the foregoing general formula which are colourless, white or pale yellow have been found to possess a strong bluish fluorescence in daylight and a slightly less fluorescence in incandescent electric or similar light, and on appli cation to fibres and films they impart such fluorescence to them. The effect of applying these compounds to fibres and films is to impart a degree of brilliance to them which is attractive and. useful.- Applied to materials which are allegedly white, but of which the whiteness has a slight tinge of yellow or brown, the compounds serve to kill the yellow or brown tinge so that the apparent whiteness of the materials is very apprc ciably enhanced. This application of the materials is of especial importance, and the present invention is therefore particularly concerned with the application of the compounds to such offwhite fibres and films. It is a special advantage of the compounds 01' this invention, and especially those in which R1 or An contain a sulphom'c group, that they impart a. very desirable wl1ite ness to wool fibres, the effect being a strong resistance to fading under the action of light and a strong resistance to laundering.

Applied to dyed textile materials the com pounds have the effect of improvingthe apparent purity of the colour.

Very small quantities of the compounds are sufficient to achieve the desired improvement in the materials. Thus the whiteness of textile materials, paper and the like can be very considerably enhanced by treating the materials with a solution of one of the said compoundsin water or an organic solvent, e. g. at a solution concentra tion of 1 part in 5000 to 1 part in 100,000. Applied to wool, the compound in which R1 or Arz contains a sulphonic acid group may be used from weakly acid solution or even neutral solution and are substantive to wool from such solutions.

In order to convert the solution concentration of l in 5,000 and 1 in 100,000 o percent of compound absorbed by weight it must be assumed that the ratio of fibre to dye bath ranges from 1 to to l to 50 .andthat the dye bath is operated to exhaustion. Both of these assumptions are customary dyeing practice. Thus, taking the strongest solution envisaged, i in 5,000 and the greatest ratio of dye bath to fibre (50:1), one obtains the conditions in which the greatest amount of dye will be absorbed. In this case 50 parts of dye bath will contain 0.01 part of fluorescent compound, i. e., one part of fibre takes up 0.01 part of fluorescer, which is 1%..

Taking, on the other hand. the most dilute bath of 1 in 100,000 and the lowest ratio of fibre (10:1). the 10 partsjof bath will contain 0.0001 part of fiuorescer, i. e.,- one part of fibre takes up 0.0001 part of fluorescer. which is 0.01%. Therefore from the figures of l to 5,000 and. 1 to 100,000

4 and the normal dyeing practice an absor tion computation of 0.01 to 1% is calculated.

'In' the case of fibresor films which are not in their natural state, the compounds of this invention may be applied thereto at any stage in the manufacture of such materials. Thus in the production of artificial filaments, fibres or films by the extrusion or casting of colloid compositions, the compounds of this invention may be incorporated in such compositions before extrusion or casting so that they are uniformly dispersed throughout the products.

Alternatively the preferred fibres or films may be treated with solutions of the compounds. Thus in the treatment of textile materials the compounds may be included in any of the liquids commonly employed for dyeing, scouring, dressing and the like, and this invention includes compositions for application to textiles for such purposes which include a compound of the" foregoing formule. in conjunction with a textile dye,

detergent or other material used for treating textiles. The compounds may be applied to the materials after the normal processes of their manufacture have been completed, for example by including the compounds in domestic washing preparations.

In the case of paper and similar materials the compounds may be applied to the wood pulp or rag-fibre before such material is made into paper, or during the paper-making operation, or may be applied as a solution directly to the raw paper, or may be applied in a dressing composition, e. 'g. a baryta coating, applied to the paper.

The compounds referred to above in which neither R3 nor Ar: contains a sulphonlc or carbcxylic group fluoresce strongly in organic solvents and may be applied to protein and polyamide fibres from an organic solvent or aqueous organic solvent, e. g. aqueous ethyl alcohol or aqueous acetic acid. These compounds, by reason of their solubility in organic solvents, are also especially adapted for inclusion in solutions of cellulose acetate and similar materials which are to be extruded or cast to form fibres or films;

One important application of the invention is in the treatment of photographic prints'where application of a solution of a compound of the foregoing general formula has the effect of whitening the highlights of the print. Considerable effort has hitherto been directed to the produc--- tion of prints having brilliant highlights, and the present invention provides a simple method whereby this result may be achieved. However, the compounds may, if desired, be incorporated in the photographic emulsions, or sub-coat or supercoat layers, prior to coating such layers to form the photographic element.

cornpound. according to this invention the tone may be changed to resemble very closely the cold tone commonly associated with prints made on paper coated with silver chloride emulsions.

The compounds of this invention may also be applied to films coated on supports, for example to finished photographic films or plates where the gelatin film takes up the compound and is photographic thereby caused to fluoresce and the image to appear colder in tone. What we claim is:

1. A process 'for improving fibres and films which comprises applying thereto a dispersion in a liquid medium of a white fluorescent compound of the general formula:

" nic eflxr,

l klg wherein R1 is selected from the class consisting of the hydrogen atom, alkyl, unsubstituted phenyl and phenyl containing alkyl, alkoxy, chloro and sulphonic substituents, Ari is selected from the class consisting of unsubstituted phenyl and phenyl containing halogen, alkyl, alkoxy and phenoxy substituents, and Ara is selected from the class consisting of unsubstituted phenyl and phenyl containing halogen, alkyl, sulphonic and acetylamino substituents, so that the said fibres and films absorb 0.01 to 1% by weight of the said compound.

2. A process for improving fibres and films which comprises applying thereto an aqueous solution of a white fluorescent compound of the general formula:

wherein R1 is selected from the class consisting of the hydrogen atom, alkyl, unsubstituted phenyl and phenyl containing alkyl, alkoxy, chloro and sulphonic substituents, Ari is selected from the class consisting of unsubstituted phenyl and phenyl containing halogen, alkyl, alkoxy and phenoxy substituents, and M2 is selected from the class consisting of unsubstituted phenyl and phenyl containing halogen, alkyl, sulphonic and acetylamino substituents, so that the said fibres and films absorb 0.01 to 1% by weight of the said compound.

3. A process for improving fibres and films which comprises applying thereto an aqueous solution of a fluorescent compound of the general formula:

II N I An wherein R1 is selectedfrom the class consisting of the hydrogen atom, alkyl, unsubstituted 61' phenyl and phenyl containing alkyl, alkoxy, chloro and sulphonic substituents, ,Ar1 is selected from the class consisting of. unsubstituted phenyl and phenyl containing halogen, alkyl, alkoxy 1 and phenoxy substituents, and A12 is selected from the class consisting of unsubstituted phenyl and phenyl containing halogen, alkyl,-sulphonic and acetylamino substituents, so that the said fibres and films absorb 0.01 to 1% by'weight of the said compound.

5. A process for improving the whiteness of wool fibres and woollen textile materials which comprises applying thereto an aqueous solution of a compound of the general formula:

All

wherein R1 is a sulphonated phenyl group, An is selected from the class consisting of unsubstituted phenyl and phenyl containing halogen, alkyl, alkoxy and phenoxy substituents, and

Arz is selected from the class consisting of unsubstituted phenyl and phenyl containing halogen, alkyl, sulphonic and acetylamino substituents, so that the said fibres and films absorb 0.01 to 1% by weight of the said compound.

6. Thin flexible organic materials for use in textiles and photographic printing containing 0.01 to 1% of a white fluorescent compound of the general formula:

from the class consisting of unsubstituted phenyl and phenyl containing halogen, alkyl, sulphonic and acetylamino substituents.

'7. Woollen textile materials having adsorbed, thereto 0.01 to 1% of a white fluorescent com-' pound of the general formula:

I An

wherein R1 is selected from the class consisting of the hydrogen atom, alkyl, unsubstituted phenyl and phenyl containing alkyl, alkoxy, chloro and sulphonic substituents, Ari is selected from the class consisting of unsubstituted phenyl and phenyl containing halogen, alkyl, alkoxy and phenoxy substituents, and An is selected from the class, consisting of unsubstituted phenyl and phenyl containing halogen, alkyl, sulphonic andacetylamino substituents. i

8. Woollen textile materials having adsorbed,

7 thereto 0.01 to 1% of'a white fluorescent compound of the general formula H;C o-Ar, m-nc- N t Ara wherein R1 is a sulphonated phenyl group, Ar is selected from the class consisting of unsubstituted phenyl and phenyl containing halogen, alkyl, alkoxy and phenoxy substituents, and A1: is selected from the'class consisting of unsubstituted phenyl and phenyl containing halogen, alkyl, sulphonic and acetylamino substituents.

9. Photographic light-sensitive materials having adsorbed thereto 0.01 to 1% by weight of a fluorescent compound of the general formula:

Ara wherein R1 is selected from the classconsisting of the hydrogen atom, alkyl, unsubstituted phenyl and phenyl containing alkyl, alkoxy, chloro and sulphonic substituents, AT]. is selected from the class consisting of unsubstituted phenyl and phenyl containing halogen, alkyl, alkoxy and phenoxy substituents, and 'Alz is selected from the class consisting of unsubstituted phenyl and phenyl containing halogen, alkyl, sulphonic and acetylamino substituents.

10. Photographic printing paper having adsorbed thereto 0.01 to 1% by weight of a compound of the general formula:

wherein R1 is selected from the class consisting of the hydrogen atom, alkyl, unsubstituted phenyl and phenyl containing alkyl, alkoxy, chloro and sulphonic substituents, Ari is selected from the class consisting of unsubstituted phenyl and phenyl containing halogen, alkyl, alkoxy and phenoxy substituents, and Arz is selected from. the class consisting of unsubstituted phenyl and,

phenyl containing halogen, alkyl, sulphonic and acetylamino substitue'nts.

11. Process for improving the whiteness of the highlights of photographic prints on paper which comprises treating the prints with a dilute solution of a compound of the formula:

H3C C-Afl wherein R1 is selected from the class consisting of the hydrogen atom, alkyl, unsubstituted phenyl and phenyl containing alkyl, alkoxy, chloro and sulphonic substituents, Ari is selected from the class consisting of unsubstituted phenyl and phenyl containing halogen, alkyl, alkoxy and phenoxy substituents, and Ar: i selected from the class consisting of unsubstituted phenyl and phenyl containing halogen, alkyl, sulphonic and' acetylamino substituents, so that the said fibres 8 and films absorb 0.01 to 1% by weighto! the said compound.

12. A process for improving fibres and, films which comprises applying thereto a dispersion in a liquid medium of a white fluorescent compound of the general formula:

wherein R1 is selected from the class consisting of the hydrogen atom, methyl, phenyl, methylphenyl, methoxyphenyl, chlorophenyl and sulphophenyl groups, X1 represents at least one substituent group selected from the class consisting of hydrogen, halogen, methyl, methoxy, ethoxy and phenoxy, and X2 represents at least one substituent group selected from the class consisting of hydrogen, halogen, methyl, sulphonic and acetylamino groups, so that the said fibres and films absorb 0.01 to 1% by weight of the said compound.

13. Thin flexible organic materials for use in textiles and photographic printing containing 0.01 to 1% of a white fluorescent compound of the general formula:

wherein R1 is selected from the class consisting of the hydrogen atom, methyl, phenyl, methylphenyl, methoxyphenyl, chlorophenyl and sulphophenyl groups, X1 represents at least one substituent group selected from the class consisting of hydrogen, halogen, methyl, methoxy, ethoxy and phenoxy, and X2 represents at least one substituent group selected from the class consisting of hydrogen, halogen, methyl, sulphonic and acetylamino groups.

JOHN DAVID KENDALL. GEORGE FRANK DUFFIN.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,153,615 Dahlen et al Aug. 11, 1939 FOREIGN PATENTS Number Country Date 566,810 Great Britain Jan. 15, 1945 OTHER REFERENCES Beilstein (Vierte Auflauge-vol. 23- 168, citing Berichte 54 (1921), 1011 and Berichte 59 (1926) 611.

Samuels et al., Journal Society Dyers Colourists, August 1947, p. 266.

Richardson, Journal Society Dyers Colour- 'ists, September 1948, p. 315. 

9. PHOTOGRAPHIC LIGHT-SENSITIVE MATERIALS HAVING ADSORBED THERETO 0.01 TO 1% BY WEIGHT OF A FLUORESCENT COMPOUND OF THE GENERAL FORMULA: 